# GMAT Tip of the Week: Just Get Started

It’s a time-honored tradition in  the Veritas Prep office: Every Friday, your author is responsible for a GMAT Tip of the Week post. And every Friday morning, he gets a cup of coffee, check his email, opens the “add new blog post” link for this blog, and sits for a few minutes staring at the blank screen.  And every Friday morning, another of this blog’s authors sits a row behind him, chuckling at the tradition and the visual of a blogger staring at an empty screen looking for inspiration.  He’s laughing right now, in fact.

This scene is also quite common on the GMAT, as examinees often read a question, get to the end of the prompt, take a second to think “wow, that’s a tough question,” and then…sit, stunned or perplexed or deep-in-thought, waiting for that stroke of inspiration to guide them.  And while another blog author sitting behind you isn’t laughing, somewhere a GMAT question author once laughed knowing that you’d approach the question this way, losing valuable time and breeding unwanted stress while you stare at the screen or at your noteboard.  This, too, is a time-honored tradition.

To combat it, you have to “do something.”  Only catsup (ketchup?) heiresses truly believe that “the best things come to those who wait.”  In truth, the best things come to those who go get them, and perhaps nowhere is this as true as on the GMAT, where that stroke of divine inspiration typically happens on the third step.

Consider this question, which comes from the Official Guide for GMAT Review, 12th Edition:

If 1/x  –  1/(x+1) = 1/(x+4), then x could be

(A) 0
(B) -1
(C) -2
(D) -3
(E) -4

A  great deal of this problem’s difficulty comes from the fact that it is abstract.  “x could be” in the question stem seems to suggest that we’re not solving for one exact value of x, but rather one possible value of x.  And the presence of three different denominators, each with a variable, makes combining like terms difficult.  But instead of staring at the question, we can get started.  Perhaps by:

1) Trying to combine like terms.  But without knowing values of x, x+1, and x+4, trying to find a common denominator is futile.  If x is 1, then the common denominator of 1/(x+1) and 1/(x+4) is 1/2 vs. 1/5 —> common denominator of 10.  But if x were 2, then we’d be looking at 1/3 and 1/6, and a common denominator of 6.  We can’t quite ascertain an algebraic way to find a common denominator — but by trying we’ve realized that we probably don’t want to solve this one algebraically.  That investment of 30 seconds will pay off — we now know what not to do!

2) Looking at answer choices.  Why are they all either 0 or negative?  If we try 0, we realize that we have 1/0 + 1/(x+1) = 1/(x+4) —but we can’t divide by 0!  So that eliminates 0, -1, and -4 as choices.  Now we only have two choices, and if we try the first, -2, we realize that it works:

1/(-2) + 1/(-1) = 1/(2)   —> TRUE